REFERENCE TO PRIORITY APPLICATIONThis application claims priority to Korean Application Serial No. 2003-39226, filed Jun. 17, 2003, the disclosure of which is hereby incorporated herein by reference.[0001]
FIELD OF THE INVENTIONThe present invention relates to integrated circuit devices and, more particularly, to multi-bank integrated circuit memory devices.[0002]
BACKGROUND OF THE INVENTIONIntegrated circuit memory devices containing multiple banks of memory arrays frequently utilize shared data routing circuitry to support efficient write and read operations. An example of a data routing circuit that is shared by multiple memory arrays is illustrated by FIG. 1. In particular, FIG. 1 illustrates an input/output[0003]data routing circuit20 that is electrically coupled to a pair ofmemory cell arrays10aand10b, which are shown as including dynamic random access (DRAM) memory cells (MC). The illustrated memory cells MC in the pair ofmemory cell arrays10aand10bare electrically coupled to the input/outputdata routing circuit20 by respective pairs of differential bit lines BL and /BL.
The input/output[0004]data routing circuit20 includes left and right equalization andisolation circuits12aand12bthat are electrically coupled by corresponding pairs of differential bit lines BL and /BL to respective columns of memory cells within thememory cell arrays10aand10b.The left equalization andisolation circuit12ais illustrated as including three NMOS equalization transistors that are responsive to an active high first equalization signal PEQi. Switching this first equalization signal PEQi from low-to-high operates to pull the corresponding bit lines to an equivalent voltage Vequal having a magnitude about equal to a voltage of the VBL reference line (e.g., Vequal=VBL−Vth, where Vth is a threshold voltage of an NMOS transistor). The left equalization andisolation circuit12aalso includes a pair of NMOS pass transistors that are responsive to a first isolation signal PISOi. When the first isolation signal PISOi is switched low-to-high, the pair of differential bit lines BL and /BL from the leftmemory cell array10aare electrically connected to a pair of differential sense bit lines SBL and /SBL. Similarly, the right equalization andisolation circuit12bis illustrated as including three NMOS equalization transistors that are responsive to an active high second equalization signal PEQj. Switching of this second equalization signal PEQj from low-to-high operates to pull the corresponding bit lines to the equivalent voltage Vequal. The right equalization andisolation circuit12balso includes a pair of NMOS pass transistors that are responsive to a second isolation signal PISOj. When the second isolation signal is switched low-to-high, the pair of differential bit lines BL and /BL from the rightmemory cell array10bare electrically connected to the pair of differential sense bit lines SBL and /SBL. As will be understood by those skilled in the art, in order to provide adequate isolation between the memory arrays, the first and second isolation signals are not active during overlapping time intervals.
A P-type[0005]sense amplifier block14 and an N-typesense amplifier block18 collectively form a sense amplifier that is responsive to a pair of complementary control signals LA and LAB. When the control signal LA is switched low-to-high and the control signal LAB is switched high-to-low, the P-typesense amplifier block14 and the N-typesense amplifier block18 become active and operate to sense and amplify any differential signal established across the pair of sense bit lines SBL and /SBL. A columnselect IO block16 is also provided in a column gate region (CGR). This column selectIO block16 includes a pair of NMOS transistors that are responsive to a column select signal (shown as CSL0). When the illustrated column select signal CSL0 is switched low-to-high, a rail-to-rail signal established across the sense bit lines SBL and /SBL is transferred to a pair of input/output lines IO and IOB during a read operation (or vice versa during a write operation). These input/output lines IO and IOB are illustrated as extending orthogonal to the bit lines BL and BLB. These and other aspects of the input/output data routing circuit of FIG.1 are more fully described in commonly assigned U.S. Pat. Nos. 5,701,268, 6,046,950 and 6,396,756. Multi-bank memory devices with input/output routing circuitry are also disclosed in commonly assigned U.S. Pat. Nos. 5,485,426, 5,949,697, 6,067,270 and 6,327,214.
The layout of the input/output[0006]data routing circuit20 of FIG. 1 may result in many closely spaced pairs of input/output lines IO and IOB when multipledata routing circuits20 are positioned side-by-side in the direction of the input/output lines IO and IOB. An example of a memory device that utilizes closely spaced input/output lines IO and IOB is illustrated by FIG. 2, which is a reproduction of FIG. 3 of U.S. Pat. No. 6,345,011 to Joo et al. In FIG. 2, a multi-bank memory device is illustrated as including memory banks MB0, MB1 and MB2. A first sense amplifier block SABLK0 extends between memory banks MB0 and MB1 and a second sense amplifier block SABLK1 extends between memory banks MB1 and MB2. These memory banks are illustrated has having 2052 pairs of bit lines (BL0, /BL0 to BL2051, /BL2051), with the even pairs of bit lines extending to one sense amplifier block and the odd pairs of bit lines extending to another sense amplifier block. Each of the sense amplifier blocks SABLK0 and SABLK1 includes a left sidebit isolation circuit50, a right sidebit isolation circuit60 and a bit line precharging andequalization circuit70 of conventional design (see, e.g., FIG. 1). A P-typesense amplifier circuit80 and an N-typesense amplifier circuit90 are also provided on opposite sides of a columnselect IO circuit100, which is responsive to column select signals (e.g., CSL0-CSL512). The column selectIO circuit100 is illustrated as including a plurality of column select IO blocks that are arranged side-by-side in a single row, with each block including a pair of column selection transistors (GT). Each pair of column selection transistors GT routes data from a corresponding pair of sense bit lines to a respective pair of closely spaced input/output (IO) lines, shown as (IOi, /IOi), (IOj, /IOj), (IOk,/IOk) and (IOl, /IOl), and vice versa, when a respective column select signal is active.
Unfortunately, such close spacing of the IO lines can result in reliability failures when a sufficient layout pitch is not maintained between the adjacent lines. To address this possibility of reliability failures, the layout area of the column[0007]select IO circuit100 can be increased, but such area increases result in lower integration densities and/or lower memory bandwidth, which is a function of memory speed and data path bandwidth.
One attempt to address the reliability and/or data path bandwidth limitations associated with the memory device of FIG. 2 utilizes the column select IO circuit of FIG. 3, which is a reproduction of FIG. 5 of the Joo et al. patent. As illustrated by FIG. 3, an[0008]interface region200 is provided between upper array (UA) portions of the memory blocks and lower array (LA) portions of the memory blocks. Thisinterface region200 provides sufficient area to reroute input/output lines IOi, IOj, /IOi and /IOj associated with the upper array (UA) away from the input/output lines IOk, IOl, /IOk and /IOl associated with the lower array (LA), and thereby maintain sufficient pitch between adjacent IO lines. However, as illustrated by FIGS. 6B and 6C of the Joo et al. patent, the rerouting of input/output lines may require the use of additional levels of metallization and contact vias and thereby complicate the process for fabricating the memory device. Moreover, the rerouting of the input/output lines may require a greater layout area to accommodate theinterface region200.
SUMMARY OF THE INVENTIONIntegrated circuit memory devices according to embodiments of the present invention include sense amplifier arrays having layouts that are configured to support greater pitch between adjacent input/output lines, while maintaining high levels of integration density. In these embodiments, a sense amplifier array is provided having first and second column select I/O blocks that are arranged in an alternating zig-zag layout sequence, with the first column select I/O blocks positioned in a first row of the sense amplifier array and the second column select I/O blocks positioned in a second row of the sense amplifier array. The first and second rows of the sense amplifier array may be immediately adjacent rows within the sense amplifier array or may be separated by one or more rows containing additional logic blocks. The sense amplifier array also includes an alternating zig-zag layout sequence of first and second N-type (or P-type) sense amplifier blocks that extends back-and-forth between the first and second rows. The zig-zag layout sequence of sense amplifier blocks is interleaved with the zig-zag layout sequence of the column select I/O blocks in a criss-cross manner. According to some additional embodiments of the present invention, the first column select I/O blocks are grouped in pairs and the second column select I/O blocks are grouped in pairs within the sense amplifier array. Similarly, the first sense amplifier blocks may be grouped in pairs and the second sense amplifier blocks may be grouped in pairs.[0009]
The column select I/O blocks are responsive to column select signals (CSL) provided on column select signal lines. The layout of the column select I/O blocks and the sense amplifier blocks may be configured so that a first column select line extends between a first column select I/O block and a first N-type (or P-type) sense amplifier block in the first row and also extends between a second column select I/O block and a second N-type (or P-type) sense amplifier block in the second row. A first column select line extension may also be provided, which is electrically connected to the first column select line. This first column select line extension may extend between the first and second rows in an orthogonal direction relative to the first column select line and may comprise polycrystalline silicon (i.e., gate polysilicon (GP)).[0010]
Additional embodiments of the present invention include an integrated circuit memory device having at least first and second memory blocks therein. These first and second memory blocks are electrically coupled by respective pairs of bit lines (BL) to a shared sense amplifier array. This sense amplifier array includes an alternating zig-zag layout sequence of first and second column select I/O blocks therein that extends back-and-forth between first and second adjacent rows of the sense amplifier array. Each of these column select I/O blocks is electrically coupled by a respective pair of sense bit lines (SBL) to a respective N-type sense amplifier block and/or P-type sense amplifier block. The sense amplifier array may also include a first plurality of isolation blocks, which are electrically coupled to first ends of a plurality of pairs of sense bit lines and to the bit lines associated with the first memory block, and a second plurality of isolation blocks, which are electrically coupled to second ends of a the plurality of pairs of sense bit lines and to the bits lines associated with the second memory block. Moreover, this sense amplifier array may be configured as a plurality of sense amplifier blocks (SABLK), which are configured as column-to-I/O control blocks. In particular, a first column-to-I/O control block may be provided with a first pair of sense bit lines that are electrically coupled to a first column select I/O block and a first N-type (P-type) sense amplifier block. In addition, a second column-to-I/O control block may be provided with a second pair of sense bit lines that are electrically coupled to a second column select I/O block, which extends opposite the first N-type (P-type) sense amplifier block, and a second N-type (P-type) sense amplifier block, which extends opposite the first column select I/O block.[0011]
Still further embodiments of the present invention include a sense amplifier array having a criss-cross arrangement of column select I/O blocks and sense amplifier blocks therein that collectively form a unit cell layout structure having first and third quadrants that contain first and second column select I/O blocks, respectively, and second and fourth quadrants that contain first and second sense amplifier blocks, respectively. Here, the first column select I/O block includes a first pair of transistors that are configured to electrically connect a first pair of sense bit lines to a first pair of I/O lines in response to a first column select signal. Similarly, the second column select I/O block includes a second pair of transistors that are configured to electrically connect a second pair of sense bit lines to a second pair of I/O lines in response to the first column select signal.[0012]
BRIEF DESCRIPTION OF THE DRAWINGSFIG. 1 is an electrical schematic of a conventional input/output data routing circuit.[0013]
FIG. 2 is an electrical schematic of a memory device that utilizes a conventional input/output data routing circuit, which is similar to the input/output data routing circuit of FIG. 1.[0014]
FIG. 3 is an electrical schematic of a memory device that utilizes another conventional input/output data routing circuit.[0015]
FIG. 4A is a block diagram of a memory device having an input/output data routing circuit according to an embodiment of the present invention.[0016]
FIG. 4B is an electrical schematic of a portion of the input/output data routing circuit of FIG. 4A.[0017]
FIG. 5A is a block diagram of a memory device having an input/output data routing circuit according to another embodiment of the present invention.[0018]
FIG. 5B is an electrical schematic of a portion of the input/output data routing circuit of FIG. 5A.[0019]
FIG. 6 is an electrical schematic of a memory device that utilizes a zig-zag arrangement of P-type sense amplifier blocks within an input/output data routing circuit, according to embodiments of the present invention.[0020]
FIG. 7 is an electrical schematic of a memory device that utilizes a zig-zag arrangement of P-type sense amplifier blocks arranged in pairs within an input/output data routing circuit, according to embodiments of the present invention.[0021]
FIG. 8 is an electrical schematic that illustrates a layout arrangement of the four column select I/O blocks shown in the zeroth sense amplifier region illustrated by FIG. 4B.[0022]
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTSThe present invention now will be described more fully herein with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like reference numerals refer to like elements throughout and signal lines and signals thereon may be referred to by the same reference characters. Signals may also be synchronized and/or undergo minor boolean operations (e.g., inversion) without being considered different signals. The suffix B (or prefix symbol “/”) to a signal name may also denote a complementary data or information signal or an active low control signal.[0023]
Referring now to FIGS. 4A-4B, an integrated[0024]circuit memory device400 according to an embodiment of the present invention will be described. Thememory device400 is illustrated as including a plurality of memory banks (e.g., arrays), which are shown as MB0, MB1 and MB2. The even pairs of bit lines ((BL0, BL0B), . . . (BL6, BL6B)) that extend from each column of MBO and MB1 are electrically coupled to a corresponding plurality of sense amplifier blocks (SABLK). These sense amplifier blocks, which are arranged side-by-side in a zeroth sense amplifier region (SAR0), operate as respective column-to-I/O control blocks having isolation blocks, equalization blocks, sense amplifier blocks and column select I/O blocks therein. Likewise, the odd pairs of bit lines ((BL1, BL1B), . . . , (BL7, BL7B)) that extend from each column of MB1 and MB2 are electrically coupled to a corresponding plurality of sense amplifier blocks SABLK, which are arranged side-by-side in a first sense amplifier region (SAR1). The zeroth sense amplifier region SAR0 includes first and second rows of blocks. The first row of blocks in SAR0 is associated with a plurality of input/output lines IO0, IO0B, IO1, IO1B and a control line LANG. The second row of blocks in SAR0 is associated with a plurality of input/output lines IO2, IO2B, IO3, IO3B and a control line LANG. The first sense amplifier region SAR1 also includes first and second rows of blocks. The first row of blocks in SAR1 is associated with a plurality of input/output lines IO4, IO4B, IO5, IO5B and a control line LANG and the second row of blocks is associated with a plurality of input/output lines IO6, IO6B, IO7, IO7B and a control line LANG. As illustrated more fully by FIG. 3 of commonly assigned U.S. Pat. No. 5,701,268, corresponding control signals provided on the control lines LANG may be used to generate the control signal LAB, which is used by N-type sense amplifier blocks (see, e.g., the N-typesense amplifier block18 in FIG. 1). Similarly, as illustrated by FIGS. 6-7, control signals provided on the control lines LAPG may be used to generate the control signals LA, which is used by P-type sense amplifier blocks (see, e.g., the P-typesense amplifier block14 in FIG. 1).
Each sense amplifier block SABLK is illustrated as including a first bit line equalization and isolation block[0025]110 and a second bit line equalization andisolation block120, which may be configured in accordance with the equalization andisolation circuits12aand12bof FIG. 1. Each sense amplifier block SABLK also includes a P-typesense amplifier block130, an N-typesense amplifier block140 and a column select IO block150, which may be configured in accordance with the corresponding blocks of FIG. 1. However, to increase input/output line routing efficiency, the column select IO blocks150 and the N-type sense amplifier blocks140 are arranged in a zig-zag layout pattern that spans the first and second rows of the zeroth sense amplifier region SAR0. Equivalent column select IO blocks150 and N-type sense amplifier blocks140 are also arranged in a zig-zag layout pattern that spans the first and second rows of the first sense amplifier region SAR1.
This zig-zag arrangement of the N-type sense amplifier blocks[0026]140 and the column select IO blocks150 is more fully illustrated by FIG. 4B, which is a detailed electrical schematic of the zeroth sense amplifier region SAR0 of FIG. 4A. In particular, FIG. 4B illustrates four column select IO blocks150 that are responsive to a zeroth column select signal CSL0. Two of these column select IO blocks150 are disposed in the first row of SAR0 and the other two are disposed in the second row of SAR0. Collectively, the illustrated column select IO blocks150 are arranged in a zig-zag pattern, as illustrated. The column select IO block150 associated with the zeroth pair of sense bit lines SBL0 and SBL0B includes two column selection transistors GT, which electrically connect the sense bit lines SBL0 and SBL0B to the zeroth pair of input/output lines IO0 and IO0B when the zeroth column select signal CSL0 is set to an active high level. The column select IO block150 associated with the fourth pair of sense bit lines SBL4 and SBL4B includes two column selection transistors GT, which electrically connect the sense bit lines SBL4 and SBL4B to the first pair of input/output lines IO1 and IO1B when the zeroth column select signal CSL0 is set to an active high level. Similarly, the column select IO block150 associated with the second pair of sense bit lines SBL2 and SBL2B includes two column selection transistors GT, which electrically connect the sense bit lines SBL2 and SBL2B to the second pair of input/output lines IO2 and IO2B when the zeroth column select signal CSL0 is set to an active high level. Finally, the column select IO block150 associated with the sixth pair of sense bit lines SBL6 and SBL6B includes two column selection transistors GT, which electrically connect the sense bit lines SBL6 and SBL6B to the first pair of input/output lines IO3 and IO3B when the zeroth column select signal CSL0 is set to an active high level.
FIG. 4B also illustrates how the zig-zag arrangement of the column select IO blocks[0027]150 is interleaved with a zig-zap arrangement of the N-type sense amplifier blocks140, which are each electrically coupled to a respective even pair of sense bit lines. This interleaved zig-zag arrangement of the N-type sense amplifier blocks140 and the column select IO blocks150 supports four pairs of input/output lines IO0/IO0B, IO1/IO1B, IO2/IO2B and IO3/IO3B, which may be configured to have wider layout pitch vis-a-vis the four pairs of input/output lines associated with the zeroth sense amplifier block SABLK0 in FIG. 2. In FIG. 4B, the two column select IO blocks150 and the two N-type sense amplifier blocks140 that are associated with two adjacent pairs of sense bit lines (e.g., SBL0/SBL0B and SBL2/SBL2B) are arranged in quadrants I-IV of a square layout cell.
The layout of the four column IO blocks[0028]150 of FIG. 4B is further illustrated by the detailed electrical schematic of FIG. 8, which shows thelayout arrangement800 of eight (8) column selection transistors GT. These column selection transistors GT are grouped in pairs within eachblock150, and each pair of transistors is electrically connected to a respective pair of sense bit lines SBL0/SBL0B, SBL2/SBL2B, SBL4/SBL4B and SBL6/SBL6B. The column selection transistors are illustrated as NMOS transistors having gate terminals that are electrically connected together by a common gate line, which is shown as a polycrystalline silicon line (i.e., gate polysilicon (GP)). This common gate line may comprise a column select line extension that extends between the first and second rows and is electrically connected to a column select line (shown as CSL0 in FIG. 4B), which may be formed at a higher level of metallization and joined to the extension by a interconnect via.
Referring now to FIGS. 5A-5B, an integrated[0029]circuit memory device500 according to another embodiment of the present invention will be described. Thememory device500 of FIGS. 5A-5B is similar to thememory device400 of FIGS. 4A-4B, however, each column select IO block150 is arranged as a pair of column select IO blocks150athat are arranged in the same row. Similarly, each N-typesense amplifier block140 is arranged as a pair of N-type sense amplifier blocks140a.Accordingly, the pair of column select IO blocks150aassociated with the zeroth and second pair of sense bit lines SBL0/SBL0B and SBL2/SBL2B includes four column selection transistors GT, which electrically connect the sense bit lines SBL0/SBL0B and SBL2/SBL2B to the zeroth and first pairs of input/output lines IO0/IO0B and IO1/IO1B when the zeroth column select signal CSL0 is set to an active high level. Similarly, the column select IO blocks150aassociated with the fourth and sixth pair of sense bit lines SBL4/SBL4B and SBL6/SBL6B includes four column selection transistors GT, which electrically connect the sense bit lines SBL4/SBL4B and SBL6/SBL6B to the second and third pairs of input/output lines IO2/IO2B and IO3/IO3B when the zeroth column select signal CSL0 is set to an active high level. Like the zig-zag arrangement of FIGS. 4A-4B, the paired zig-zag arrangement of the N-type sense amplifier blocks140aand column select IO blocks150asupports four pairs of input/output lines IO0/IO0B, IO1/IO1B, IO2/IO2B and IO3/IO3B.
Referring now to FIG. 6, an integrated[0030]circuit memory device600 according to another embodiment of the present invention is similar to thememory device400 of FIG. 4A, however, the positions of the N-type sense amplifier blocks140 and the P-type sense amplifier blocks130 within SAR0 and SAR1 are reversed. Thus, in FIG. 6, the P-type sense amplifier blocks130 are arranged in a zig-zag pattern in the first and second rows of SAR0 and SAR1. Similarly, in FIG. 7, an integratedcircuit memory device700 is illustrated, which is similar to thememory device500 of FIG. 5A, however, the positions of the pairs of N-type sense amplifier blocks140aand P-type sense amplifier blocks150aare reversed.
In the drawings and specification, there have been disclosed typical preferred embodiments of the invention and, although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being set forth in the following claims.[0031]